The present invention relates to a new and distinct variety of semi-evergreen azalea of the genus Rhododendron and a member of the Ericaceae family. It was produced by Paul A. Kohl as a side interest to his work as a horticulturist. The plant was selected by him from a group of seedlings which resulted from his cross-pollination of various species. He continued to produce identical plants in St. Louis, Mo. by means of cuttings from the original seedling.
The value of this new cultivar lies in its uniform color, fine shape, adaptability to the heavy soil of the St. Louis area, and its hardiness in a place notorious for the extremes of a capricious climate.
The specific parentage of the new variety is unknown because the hybridizer kept no known records of the background, parentage and crosses which resulted in the new plant.
The applicant has compared it to similar plants offered in plant catalogues and several known examples. The Azalea hybrid "Paul A. Kohl" appears to be an "azalea mucronatum". The flower shape is similar to Rhododendron schlippenbachii, the "Royal Azalea", but schlippenbachii is lighter pink with white stamens and pistil while Azalea hybrid plant "Paul A. Kohl" has pink stamens and Rhodium pistil. Schlippenbachii is more open-branched while the subject cultivar is very compact.
Working from a catalogue from "Wayside Gardens", the color of the flower is similar to "Ellie Harris" which shows the deep red pistil. "Ellie Harris" is a hose-in-hose azalea; the subject plant is single and of deeper color.
Azalea hybrid plant "Paul A. Kohl" resembles "Gables Tall Lavender" #892299 except that "Gables" has red speckling on uppermost petal while Azalea hybrid plant "Paul A. Kohl" has no visible variation in color.
The subject azalea is similar to the "Torch Azalea", Rhododendron kaempferi "Atlanta", but this flower is a deeper pink with slight speckling and a more pointy and narrower leaf.
This new hybrid has the following combination of characteristics which distinguish it from other varieties:
1. Flower color is a completely uniform pink with no variant shading, giving it a formal appearance. Flower size is 1 31/32 to 2 15/32 inchs, usually 1 31/32 to 2 5/32 inches from petal tip to petal tip. It blooms from early April to mid-May, depending on the season.
2. The plant is vigorous in growth and exceptionally hardy, withstanding years of cold, heat, drought and excessive moisture experienced in the St. Louis area. The plant has survived temperatures as low as -10.degree. F. and periods of consecutive days below the zero mark. The plant has survived a sudden drop in temperature from warm days at the end of October to 8.degree. F. on the eighth of November. This acute change killed many other plants in and around St. Louis.
3. Ease of vegetative propogation by softwood cuttings: The plant was successfully propagated by Paul A. Kohl in St. Louis, Mo., and the specimens that he propagated are those shown in the accompanying photographs. Paul A. Kohl tested the plant in St. Louis and determined it to be stable. Each clonal progeny exhibited identical characteristics of the mother plant, establishing the hybrid as reproducible and true to type .